This invention relates to fabric softening compositions and, in particular, to granular compositions which readily form aqueous emulsions and/or dispersions when added to water.
It has long been recognized that certain chemical compounds have the capability of imparting softness to textile fabrics. These compounds, which are known generally as "softening agents," "fabric softeners," or "softeners," have been used both by the textile industry and by housewives in the laundry to soften a finished fabric, thereby making the fabric smooth, pliable and fluffy to handle. In addition to the quality of softness, the fabrics frequently have a reduced tendency to static cling and are easier to iron.
The softening agents which are usually employed in compositions intended for use by the individual consumer are cationic surfactant compounds, commonly quaternary ammonium compounds having at least two long alkyl chains, for example, distearyl dimethyl ammonium chloride. The positive charge on the softening compound encourages its deposition onto the fabric substrate, the surface of which is usually negatively charged.
However, although the above-mentioned cationic compounds are highly effective softeners when applied in a rinse solution, they cannot be supplied in a granular form which will readily disperse to form concentrated aqueous emulsions/dispersions of the type typically employed by the individual consumer. Granules containing cationic compounds having long alkyl chains tend to form highly viscous/non-dispersible phases rather than dispersions when added to water. The present invention provides granular softening compositions, which employ nonionic softeners, which compositions provide excellent deposition onto the fabric surface from dilute aqueous solution, and which, surprisingly, can be used to form aqueous concentrated emulsions/dispersions of the type used by individual consumers by simply mixing with tap water. The compositions are sold in granular form and used by the consumer to form typical aqueous, liquid, rinse-added fabric softener compositions of the general type disclosed in U.S. Pat. Nos.: 4,128,484, Barford and Benjamin, for Fabric Softening Compositions, issued Dec. 5, 1978; and 4,126,562, Goffinet and Leclercq, for Textile Treatment Compositions, issued Nov. 21, 1978; said patents being incorporated herein by reference. Such granular compositions provide a large environmental advantage versus existing liquid products since the granular products can be packaged in cardboard cartons that are essentially biodegradable rather than in plastic bottles which are more slowly degradable.